A Peaceful World

How do you unify the land?

The leads: Conquer half the realm, then marry the person on the other side.

Content warning: The male lead is not a virgin, but the female lead is.

The historical setting is similar to the Sui and Tang dynasties, but this is a fictional world, so please don't nitpick the history.

Finally, here's a silly poem:

The realm lies ruined, the great halls fall,

Autumn troops muster as horns sound in the wind.

Through storms and flames, the wars die down,

Side by side, we bring peace to the land.

Theme: Wherever you are, strive to take control of your own destiny